Resistance of Culex pipiens pallens to insecticides and its resistance management

Objective To survey the resistance status of Culex pipiens pallens to several commonly used insecticides in Jiangsu Province,and learn how to prevent the occurrence and development of resistance. Methods Larvae of Cx.pipiens pallens were collected in the surburbs of Xuzhou,Lianyungang and Wuxi city in Jiangsu Province,then tested with WHO standard bioassay to calculate LC50 and resistance index.Results Cx.pipiens pallens was sensitive to permethrin and bioallethrin.Cx.pipiens pallens had high resistance to DDVP,the resistant index was 29.42-205.55,and Cx.pipiens pallens from these cities also had developed resistance to other insecticides in different levels.Conclusion Resistance should be monitored regularly.Insecticides should be used scientifically and rational to prevent and reduce the occurrence and development of resistance.